/*
 * Voice call audio setup tool
 *
 * Copyright (C) 2020  Ondřej Jirman <megous@megous.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * 2020-09-29: Updated for the new Samuel's digital codec driver
 */

#include <assert.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <inttypes.h>
#include <fcntl.h>
#include <sys/ioctl.h>

#include <sound/asound.h>
#include <sound/tlv.h>

#define ARRAY_SIZE(a) (sizeof((a)) / sizeof((a)[0]))

void syscall_error(int is_err, const char* fmt, ...)
{
    va_list ap;

    if (!is_err)
        return;

    printf("ERROR: ");
    va_start(ap, fmt);
    vprintf(fmt, ap);
    va_end(ap);
    printf(": %s\n", strerror(errno));

    exit(1);
}

void error(const char* fmt, ...)
{
    va_list ap;

    printf("ERROR: ");
    va_start(ap, fmt);
    vprintf(fmt, ap);
    va_end(ap);
    printf("\n");

    exit(1);
}

struct audio_control_state {
    char name[128];
    union {
        int64_t i[4];
        const char* e[4];
    } vals;
    bool used;
};

static bool audio_restore_state(struct audio_control_state* controls, int n_controls)
{
    int fd;
    int ret;

    fd = open("/dev/snd/controlC0", O_CLOEXEC | O_NONBLOCK);
    if (fd < 0)
        error("failed to open card\n");

    struct snd_ctl_elem_list el = {
        .offset = 0,
        .space = 0,
    };
    ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &el);
    syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_LIST failed");

    struct snd_ctl_elem_id ids[el.count];
    el.pids = ids;
    el.space = el.count;
    ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &el);
    syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_LIST failed");

    for (int i = 0; i < el.used; i++) {
        struct snd_ctl_elem_info inf = {
            .id = ids[i],
        };

        ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &inf);
        syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_INFO failed");

        if ((inf.access & SNDRV_CTL_ELEM_ACCESS_READ) && (inf.access & SNDRV_CTL_ELEM_ACCESS_WRITE)) {
            struct snd_ctl_elem_value val = {
                .id = ids[i],
            };
            int64_t cval = 0;

            ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_READ, &val);
            syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_READ failed");

            struct audio_control_state* cs = NULL;
            for (int j = 0; j < n_controls; j++) {
                if (!strcmp(controls[j].name, ids[i].name)) {
                    cs = &controls[j];
                    break;
                }
            }

            if (!cs) {
                printf("Control \"%s\" si not defined in the controls state\n", ids[i].name);
                continue;
            }

            cs->used = 1;

            // check if value needs changing

            switch (inf.type) {
            case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
            case SNDRV_CTL_ELEM_TYPE_INTEGER:
                for (int j = 0; j < inf.count; j++) {
                    if (cs->vals.i[j] != val.value.integer.value[j]) {
                        // update
                        //printf("%s <=[%d]= %"PRIi64"\n", ids[i].name, j, cs->vals.i[j]);

                        val.value.integer.value[j] = cs->vals.i[j];
                        ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &val);
                        syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_WRITE failed");
                    }
                }

                break;
            case SNDRV_CTL_ELEM_TYPE_INTEGER64:
                for (int j = 0; j < inf.count; j++) {
                    if (cs->vals.i[j] != val.value.integer64.value[j]) {
                        // update
                        //printf("%s <=[%d]= %"PRIi64"\n", ids[i].name, j, cs->vals.i[j]);

                        val.value.integer64.value[j] = cs->vals.i[j];
                        ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &val);
                        syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_WRITE failed");
                    }
                }

                break;

            case SNDRV_CTL_ELEM_TYPE_ENUMERATED: {
                for (int k = 0; k < inf.count; k++) {
                    int eval = -1;
                    for (int j = 0; j < inf.value.enumerated.items; j++) {
                        inf.value.enumerated.item = j;

                        ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &inf);
                        syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_INFO failed");

                        if (!strcmp(cs->vals.e[k], inf.value.enumerated.name)) {
                            eval = j;
                            break;
                        }
                    }

                    if (eval < 0)
                        error("enum value %s not found\n", cs->vals.e[k]);

                    if (eval != val.value.enumerated.item[k]) {
                        // update
                        //printf("%s <=%d= %s\n", ids[i].name, k, cs->vals.e[k]);

                        val.value.enumerated.item[k] = eval;
                        ret = ioctl(fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &val);
                        syscall_error(ret < 0, "SNDRV_CTL_IOCTL_ELEM_WRITE failed");
                    }
                }

                break;
            }
            }
        }
    }

    for (int j = 0; j < n_controls; j++)
        if (!controls[j].used)
            printf("Control \"%s\" is defined in state but not present on the card\n", controls[j].name);

    close(fd);
    return true;
}

struct audio_setup {
    bool mic_on;
    bool spk_on;
    bool hp_on;
    bool ear_on;

    // when sending audio to modem from AIF1 R, also play that back
    // to me locally (just like AIF1 L plays just to me)
    //
    // this is to monitor what SW is playing to the modem (so that
    // I can hear my robocaller talking)
    bool modem_playback_monitor;

    // enable modem routes to DAC/from ADC (spk/mic)
    // digital paths to AIF1 are always on
    bool to_modem_on;
    bool from_modem_on;

    // shut off/enable all digital paths to the modem:
    // keep this off until the call starts, then turn it on
    bool dai2_en;

    int mic_gain;
    int spk_vol;
    int ear_vol;
    int hp_vol;
};

static void audio_set_controls(struct audio_setup* s)
{
    struct audio_control_state controls[] = {
        //
        // Analog input:
        //

        // Mic 1 (daughterboard)
        { .name = "Mic1 Boost Volume",                              .vals.i = { s->mic_gain } },

        // Mic 2 (headphones)
        { .name = "Mic2 Boost Volume",                              .vals.i = { 0 } },

        // Line in (unused on PP)
        // no controls yet

        // Input mixers before ADC

        { .name = "Mic1 Capture Switch",                            .vals.i = { !!s->mic_on, !!s->mic_on } },
        { .name = "Mic2 Capture Switch",                            .vals.i = { 0, 0 } },
        { .name = "Line In Capture Switch",                         .vals.i = { 0, 0 } }, // Out Mix -> In Mix
        { .name = "Mixer Capture Switch",                           .vals.i = { 0, 0 } },
        { .name = "Mixer Reversed Capture Switch",                  .vals.i = { 0, 0 } },

        // ADC
        { .name = "ADC Gain Capture Volume",                        .vals.i = { 0 } },
        { .name = "ADC Capture Volume",                             .vals.i = { 160, 160 } }, // digital gain

        //
        // Digital paths:
        //

        // AIF1 (SoC)

        // AIF1 slot0 capture mixer sources
        { .name = "AIF1 Data Digital ADC Capture Switch",           .vals.i = { 1, 0 } },
        { .name = "AIF1 Slot 0 Digital ADC Capture Switch",         .vals.i = { 0, 0 } },
        { .name = "AIF2 Digital ADC Capture Switch",                .vals.i = { 0, 1 } },
        { .name = "AIF2 Inv Digital ADC Capture Switch",            .vals.i = { 0, 0 } }, //XXX: capture right from the left AIF2?

        // AIF1 slot0 capture/playback mono mixing/digital volume
        { .name = "AIF1 AD0 Capture Volume",                        .vals.i = { 160, 160 } },
        { .name = "AIF1 AD0 Stereo Capture Route",                  .vals.e = { "Stereo", "Stereo" } },
        { .name = "AIF1 DA0 Playback Volume",                       .vals.i = { 160, 160 } },
        { .name = "AIF1 DA0 Stereo Playback Route",                 .vals.e = { "Stereo", "Stereo" } },

        // AIF2 (modem)

        // AIF2 capture mixer sources
        { .name = "AIF2 ADC Mixer ADC Capture Switch",              .vals.i = { !!s->to_modem_on && !!s->dai2_en, 0 } }, // from adc/mic
        { .name = "AIF2 ADC Mixer AIF1 DA0 Capture Switch",         .vals.i = { 0, 1 } }, // from aif1 R
        { .name = "AIF2 ADC Mixer AIF2 DAC Rev Capture Switch",     .vals.i = { 0, 0 } },

        // AIF2 capture/playback mono mixing/digital volume
        { .name = "AIF2 ADC Capture Volume",                        .vals.i = { 160, 160 } },
        { .name = "AIF2 DAC Playback Volume",                       .vals.i = { 160, 160 } },
        { .name = "AIF2 ADC Stereo Capture Route",                  .vals.e = { "Mix Mono", "Mix Mono" } }, // we mix because we're sending two channels (from mic and AIF1 R)
        { .name = "AIF2 DAC Stereo Playback Route",                 .vals.e = { "Sum Mono", "Sum Mono" } },  // we sum because modem is sending a single channel

        // AIF3 (bluetooth)

        { .name = "AIF3 ADC Source Capture Route",                  .vals.e = { "None" } },
        { .name = "AIF2 DAC Source Playback Route",                 .vals.e = { "AIF2" } },

        // DAC

        // DAC input mixers (sources from ADC, and AIF1/2)
        { .name = "ADC Digital DAC Playback Switch",                .vals.i = { 0, 0 } }, // we don't play our mic to ourselves
        { .name = "AIF1 Slot 0 Digital DAC Playback Switch",        .vals.i = { 1, !!s->modem_playback_monitor } },
        { .name = "AIF2 Digital DAC Playback Switch",               .vals.i = { 0, !!s->dai2_en && !!s->from_modem_on } },

        //
        // Analog output:
        //

        // Output mixer after DAC

        { .name = "DAC Playback Switch",                            .vals.i = { 1, 1 } },
        { .name = "DAC Reversed Playback Switch",                   .vals.i = { 1, 1 } },
        { .name = "DAC Playback Volume",                            .vals.i = { 160, 160 } },
        { .name = "Mic1 Playback Switch",                           .vals.i = { 0, 0 } },
        { .name = "Mic1 Playback Volume",                           .vals.i = { 0 } },
        { .name = "Mic2 Playback Switch",                           .vals.i = { 0, 0 } },
        { .name = "Mic2 Playback Volume",                           .vals.i = { 0 } },
        { .name = "Line In Playback Switch",                        .vals.i = { 0, 0 } },
        { .name = "Line In Playback Volume",                        .vals.i = { 0 } },

        // Outputs

        { .name = "Earpiece Source Playback Route",		    .vals.e = { "Left Mixer" } },
        { .name = "Earpiece Playback Switch",                       .vals.i = { !!s->ear_on } },
        { .name = "Earpiece Playback Volume",                       .vals.i = { s->ear_vol } },

        { .name = "Headphone Source Playback Route",                .vals.e = { "Mixer", "Mixer" } },
        { .name = "Headphone Playback Switch",                      .vals.i = { !!s->hp_on, !!s->hp_on } },
        { .name = "Headphone Playback Volume",                      .vals.i = { s->hp_vol } },

        // Loudspeaker
        { .name = "Line Out Source Playback Route",                 .vals.e = { "Mono Differential", "Mono Differential" } },
        { .name = "Line Out Playback Switch",                       .vals.i = { !!s->spk_on, !!s->spk_on } },
        { .name = "Line Out Playback Volume",                       .vals.i = { s->spk_vol } },
    };

    audio_restore_state(controls, ARRAY_SIZE(controls));
}

static struct audio_setup audio_setup = {
    .mic_on = true,
    .ear_on = true,
    .spk_on = false,
    .hp_on = false,

    .from_modem_on = true,
    .to_modem_on = true,
    .modem_playback_monitor = false,

    .dai2_en = false,

    .hp_vol = 15,
    .spk_vol = 15,
    .ear_vol = 31,
    .mic_gain = 1,
};

int call_audio_setup()
{
#if 0
    audio_setup.spk_on = 1;
    audio_setup.mic_on = 1;
    audio_setup.hp_on = 1;
    audio_setup.ear_on = 1;
#endif
    // fprintf(stderr, "Audio setup called\n");
    audio_setup.dai2_en = 0;
    audio_set_controls(&audio_setup);
    audio_setup.dai2_en = 1;
    audio_set_controls(&audio_setup);

    return 0;
}
